Effect of Intensity Training on Plasma Ghrelin Concentration in Male Rats

Document Type : Research Paper

Authors

Abstract

Ghrelin is a gut hormone predominantly produced by the stomach and, to a lesser extent, by other regions of the gastrointestinal tract. Ghrelin circulates in the bloodstream in two different forms: acylated (n-octanoylated) and unacylated (des-octanoylated or des-acylated).  The purposes of this study were to examine the effect of intensity training on plasma ghrelin concentration in Male Rat. Forty adult Wistar male rats (8 weeks old, 28020 g) were used. Animals were randomly divided into four groups: high intensity (34m/min ~ %85-%90 Vo2max), moderate intensity (28m/min ~ %70-%75 Vo2max), low intensity (20m/min ~ %55-%65 Vo2max), and control groups. All experimental groups performed a 12 week exercise program consisted of treadmill running for 1 hr/day, 5 days/week and 0 gradient. After 12 weeks ghrelin produced was measured. Possible statistically significant differences between groups after intervention was determined by one-way ANOVA , and LSD test was used for a post hoc analysis. Ghrelin concentration increased significantly at high and moderate intensity groups (p<0.05).  Data indicate that a higher plasma acylated ghrelin in the present study might be attributed to a liver and skeletal muscle glycogen and ATP deficiency and an incomplete energy sources recovery after last exercise session which was accompanied with overnight fast.

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